Reformas constitucionales para asegurar los derechos sociales

Colorectal cancer is a curable disease when detected and treated in time. To optimise the outcome of colorectal cancer patients, accurate diagnosis and staging are important. This provides an opportunity for screening, which is already advised in the US and the UK and is

being implemented in many other European countries.6,7 _{In the end of 2009 the Dutch Health}

Council advised the government that mass screening in the Netherlands should be conducted using biannual immunochemical faecal occult blood test for men and women aged 55 to 75

years.8 _{The introduction of the screening will be between 2013 and 2019. In patients with}

a positive test result at screening, optimal diagnostics (especially colonoscopy) will follow, and, if necessary, treatment. The aim of the screening is reduced colorectal cancer mortal- ity by detecting cancers at an earlier stage. Screening will probably result in an increased workload for both gastroenterologists and pathologists, and possibly also surgeons, due to increased finding of adenomatous polyps. Besides, costs will increase due to the screening itself, as well as, the treatment of patients with a positive screening. Screening could, on the long term, result in decreased costs of colorectal cancer treatment, when tumours are found at an earlier stage. Therefore, fewer patients would be diagnosed with an advanced stage of disease, needing more extensive treatment. Overall, screening could improve outcome, but the effectiveness of screening remains under discussion, as is also the case in for example

breast cancer and prostate cancer.9 _{In breast cancer and prostate cancer the incidences have}

increased due to the introduction of screening, and have not returned to prescreening levels. Besides, the relative fraction of early stage cancer has increased, while the incidence of more

advanced tumours has not decreased. Therefore, results of the introduction of screening should be analysed carefully in order to achieve optimal results.

Once the diagnosis is established, the extent of the primary tumour, regional lymph nodes, as well as distant metastases should be determined, also called staging, to provide a framework for discussing therapy and prognosis. Besides, uniform staging provides a common language with which doctors can communicate about a patient’s case, and to compare treatment

strategies and outcomes.10 _{National clinical guidelines state that for diagnostic assessment}

of colorectal cancer all patients should undergo physical examination, colonoscopy for colon cancer and endoscopy for rectal cancer, and imaging procedures of the abdomen, liver, and

thorax. Furthermore, all patients need to be discussed in a multidisciplinary meeting.11 _Based

on the results of diagnostic assessment, the stage is determined. There are different types of staging; clinical staging, based on the physical examination, imaging tests, and biopsies of affected areas, and pathological staging, which can only be done in patients who have had surgery to remove the tumour. In pathological staging, both the information of clinical staging and the surgery are combined. Finally, since nowadays colorectal cancer patients more often are treated with neoadjuvant treatment, restaging is become more common and is used to determine the extent of the disease after neoadjuvant treatment.

Currently, the Tumour, Nodes, and Metastasis (TNM) staging system is considered the most robust tool for prediction of prognosis and for decisions on the delivery of treatment. The objectives of the TNM system have been stated as: to aid in the planning of treatment; to give some indication of prognosis; to assist in assessing the effects of treatment; to help with the exchange of information between treatment centres; and to contribute to the continuing

investigation of human cancers.12 _{Since the knowledge of cancer is continually expanding, the}

TNM system is revised every few years. Unfortunately, these revisions may cause problems, since modification of a component of the system could lead to the upstaging or downstaging of the disease, resulting in a change in treatment. Besides, changes in the TNM system can also lead to an inability to compare results from new trials with older trials, or even worse, when

the changes occur during an ongoing trial.13 _{As a result of the variation in definition of tumour}

deposit between the TNM5, TNM6 and TNM7, and their reproducibility and use in special situations, such as after neoadjuvant treatment, the Netherlands decided to continue applying

the TNM5.11,14 _{Additional information needed for optimal staging, such as the R-classification,}

has not been included in the newer TNM versions. On the other hand, an improvement of the TNM6 as compared to the TNM5 is the distinction between stage IIA and stage IIB colon cancer patients, since the patients with a T4 N0 M0 from stage IIB do indeed have worse prognosis than those classified as T3 N0 M0. These stage IIB patients, defined as high risk, are often treated with adjuvant chemotherapy. However, other patients with stage II are also defined as high risk, and should therefore receive adjuvant chemotherapy. These patients have extramural vascular invasion or extensive extramural spread, inadequately sampled nodes

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identified by the TNM-system or are compromised. In addition, it is recommended to describe which TMN version is used and whether there are tumour deposits present, and describe their

characteristics.11 _{Furthermore, additional details such as needed to confirm high risk, should}

be described. Perhaps in the future, a different staging system could be developed including possible gene mutations, which could lead to more individually based treatment and progno- sis. On the other hand, the desire is to keep the staging system simple.